Lobna Salem

Abstract

Agriculture and aquaculture play an important role in food security and water withdrawals. Agriculture and aquaculture contribute to over 70% of global water consumption. Aquaponics provides a solution for both sectors to reduce the combined water consumption and pollution and increase food production. The goal of the present study was to assess two aquaponics systems Deep-Water Culture (DWC) and Sand-Bed lettuce (Lactuca sativa variety capitata Type Batavia) production and water consumption. Each system contained a fish tank, plant bed, collection bed, three replicates per system and a mechanical filter; whereas, DWC contained an additional biological filter after the mechanical filter. The main differences assumed between DWC and Sand-Bed are Sand-Bed uses less water and does not require biological filter as sand media acts like a biological filter. Both systems had similar nitrate and ammonium concentration over 35 days period. PH, temperature, EC, SAR and DO in both systems remained within acceptable ranges compared to literature. Sand-Bed nitrifying bacteria counts were also higher than DWC's bacteria by end of study period. Results showed that the lettuce root length in DWC were nearly two-fold the root length in Sand-Bed which provides larger surface area for nutrients uptake and enhance nitrification rate by bacteria. Calcium, phosphorous, zinc, copper, magnesium and boron concentrations in lettuce samples harvested form the DWC were nearly two-times the concentrations in lettuce samples growing in Sand- Bed. The DWC Lettuce yields per m2 were 27% higher than the Sand-Bed system's lettuce of 1.42 kg/m2 in DWC and 1.04 kg/m2 in Sand-Bed system. However, the daily water consumption in DWC system was higher than Sand-Bed system. Overall, DWC system performed better by producing higher lettuce yield with higher nutritional content while consuming more water compared to Sand bed system. Therefore, the Sand-Bed system requires further research to reach productive yields like the DWC system and benefit from its reduced water consumption and the potential of growing larger variety of crops.

Degree Name

MS in Sustainable Development

Graduation Date

6-1-2019

Submission Date

May 2019

First Advisor

Hani Sewilam, Walid Fouad

Committee Member 1

Mohamed, Essam

Committee Member 2

Riad, Gamal

Extent

p.88

Document Type

Master's Thesis

Rights

The author retains all rights with regard to copyright. The author certifies that written permission from the owner(s) of third-party copyrighted matter included in the thesis, dissertation, paper, or record of study has been obtained. The author further certifies that IRB approval has been obtained for this thesis, or that IRB approval is not necessary for this thesis. Insofar as this thesis, dissertation, paper, or record of study is an educational record as defined in the Family Educational Rights and Privacy Act (FERPA) (20 USC 1232g), the author has granted consent to disclosure of it to anyone who requests a copy.

Institutional Review Board (IRB) Approval

Approval has been obtained for this item

Comments

This master thesis (research) was funded by the Center for Applied Research on the Environment and Sustainability (CARES) in the American University in Cairo and The American University in Cairo Research Grants Funds in Cairo, Egypt.

Download

Share

COinS